Method of authenticating a plurality of files linked to a text document

At least steering text document multiple testing is separated upper of the status character designation attribute, with multiple document transmission method of text document, the method comprises the steps: In aggregate of each file, efficiently obtaining hash value composed of a hash digital subset, calculates of multiple document a hash function of each of which (10); A in the cavity space subset with corresponding to each of the corresponding code hash digital of each hash digital subset, replacing the hollow cavity designation attribute, a step (16) is text document hollow cavity each subset coding of multiple, subsetsSigns (step by a common key algorithm computational code message documents' electronic 18), wherein the electronic to a signature the digital subset composed of; A by using code to signature digital replacing the hollow cavity correspondingly the designation attribute value, a coding a document the hollow cavity subset code step (20).